Surgical retractor and stabilizing device and method for use

ABSTRACT

An adjustable surgical retractor and its use for improving a surgeon&#39;s ability to perform closed-chest video-assisted exploratory, diagnostic or surgical procedures on a patient. The surgical retractor has opposable blades which can be inserted into a surgical incision in a patient undergoing a surgical procedure then spread apart to form an elongated access opening through which a instrument may be inserted to perform exploratory, diagnostic or surgical procedures. The blades used in the surgical retractor may be flexible or rigid and are attachable to the retractor. The blades are of a width, depth and thickness to provide an access to an internal cavity or subcutaneous region to allow greater degrees of freedom to the surgeon in inserting instruments into the access opening. The use of the surgical retractor forms a substantially ovoid channel, through which a medical instrument can be inserted to perform surgical or other operations.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation of application Ser. No. 10/371,756 filed Feb. 21,2003, which is a continuation of application Ser. No. 09/672,110 filedSep. 27, 2000, which is a continuation of application Ser. No.09/171,206 filed Aug. 10, 1999, which is a National Stage application ofinternational application number PCT/US97/06112 filed Apr. 10, 1997,which claimed the benefit of provisional patent application U.S.60/014,922 filed Apr. 10, 1996 in the name of inventors ArthurBertolero, Raymond Bertolero and Jerome Riebman. This application isrelated to applications PCT/US97/06533, PCT/US97/05910, PCT/US97/06070and U.S. Utility Ser. No. 08/838,774, which were concurrently or almostconcurrently filed with PCT/US97/06112, which is one of the applicationin the priority chain listed above. Each of the above-identified patentapplications is incorporated by reference.

FIELD OF THE INVENTION

This invention relates to an adjustable surgical retractor and its usefor improving a surgeon's ability to perform closed-chest,video-assisted exploratory, diagnostic or surgical procedures on apatient. The invention also relates to unique blades useful incombination with the retractor.

BACKGROUND OF THE INVENTION

Surgery on the heart is one of the most commonly performed types ofsurgery that is done in hospitals across the U.S. Cardiac surgery caninvolve the correction of defects in the valves of the heart, defects tothe veins or the arteries of the heart and defects such as aneurysms andthromboses that relate to the circulation of blood from the heart to thebody. In the past, most cardiac surgery was performed as open-chestsurgery, in which a primary median sternotomy was performed. Thatprocedure involves vertical midline skin incision from just below thesuper sternal notch to a point one to three centimeters below the tip ofthe xiphoid. This is followed by scoring the sternum with a cautery,then dividing the sternum down the midline and spreading the sternaledges to expose the area of the heart in the thoracic cavity. Thistechnique causes significant physical trauma to the patient and canrequire one week of hospital recovery time and up to eight weeks ofconvalescence. This can be very expensive in terms of hospital costs anddisability, to say nothing of the pain to the patient.

Recently, attempts have been made to change such invasive surgery tominimize the trauma to the patient, to allow the patient to recover morerapidly and to minimize the cost involved in the process. New surgicaltechniques have been developed which are less invasive and traumaticthan the standard open-chest surgery. This is generally referred to asminimally-invasive surgery. One of the key aspects of the minimallyinvasive techniques is the use of a trocar as an entry port for thesurgical instruments. In general, minimally invasive surgery entailsseveral steps: (1) at least one, and preferably at least two,intercostal incisions are made to provide an entry position for atrocar; (2) a trocar is inserted through the incision to provide anaccess channel to the region in which the surgery is to take place,e.g., the thoracic cavity; (3) a videoscope is provided through anotheraccess port to image the internal region (e.g., the heart) to beoperated on; (4) an instrument is inserted through the trocar channel,and (5) the surgeon performs the indicated surgery using the instrumentsinserted through the access channel. Prior to steps (1)-(5), the patientmay be prepared for surgery by placing him or her on a cardiopulmonarybypass (CPB) system and the appropriate anesthesia, then maintaining theCPB and anesthesia throughout the operation. See U.S. Pat. No. 5,452,733to Sterman et al. issued Sep. 26, 1995 for a discussion of thistechnique.

While this procedure has the advantage of being less invasive ortraumatic than performing a media, sternotomy, there are numerousdisadvantages to using trocars to establish the entry ports for theinstruments and viewscope. For example, the trocars are basically“screwed” into position through the intercostal incision. Thistraumatizes the local tissues and nerve cells surrounding the trocar.

Once in place, the trocar provides a narrow cylindrical channel having arelatively small circular cross-section. This minimizes the movement ofthe instrument relative to the longitudinal axis and requiresspecially-designed instruments for the surgeon to perform the desiredoperation (See, e.g., the Sterman patent U.S. Pat. No. 5,452,733). Inaddition, because of the limited movement, the surgeon often has toforce the instrument into an angle that moves the trocar and furtherdamages the surrounding tissue and nerves. The need to force theinstrument causes the surgeon to lose sensitivity and tactile feedback,thus making the surgery more difficult. The surgical retractor of thisinvention is designed to reduce the initial trauma to the patient inproviding access to the internal region, to reduce the trauma to thepatient during surgery, to provide the surgeon with greater sensitivityand tactile feedback during surgery, and to allow the surgeon to useinstruments of a more standard design in performing the non-invasivesurgery.

Other less invasive surgical techniques include access to the region ofthe heart to be corrected by anterior mediastinotomy or a thoracotomy.In a mediastinotomy, an incision is made that is two to three inches inlength of a parasternal nature on the left or the right of the patient'ssternum according to the cardiac structure that needs the attention inthe surgery. Either the third or the fourth costal cartilage is exciseddepending on the size of the heart. This provides a smaller area ofsurgical access to the heart that is generally less traumatic to thepatient. A thoracotomy is generally begun with an incision in the fourthor fifth intercostal space, i.e. the space between ribs 4 and 5 or ribs5 and 6. Once an incision is made, it is completed to lay openunderlying area by spreading the ribs. A retractor is used to enlargethe space between the ribs.

At the present time, when either of these techniques are used, aretractor is used to keep the ribs and soft tissues apart and expose thearea to be operated on to the surgeon who is then able to work in thesurgical field to perform the operation. The types of retractors thatare used may be seen, for example, in volume 1 of Cardiac Surgery byJohn W. Kirkland and Brian G. Barratt-Boyes, Second Edition, Chapter 2,at page 101. Commercial-type retractors for minimally-invasive surgerythat are useful for a mediastinotomy or a thoracotomy are manufacturedby Snowden Pencer (the ENDOCABG rib spreader and retractor), U.S.Surgical (the mini CABG system), and Cardiothoracic Systems (the CTSMIDCAB. System). The ENDOCABG retractor is two opposing retractor armsthat are interconnected by a ratchet arm having a thumbscrew which canadjust the distance between the retractor arms. While this provides auseful retractor, it has certain shortcomings in its ease of use. Themini CABG System is an oval-based platform to which a number ofretractors are then fitted around the extremity of the universal ringbase and adjusted by a gear tooth connection. Each of the retractorshave to be separately adjusted and there are other devices that can beconnected to the universal base which can aid the surgeon in damping theheart movement to better work on the artery or vessel to which thesurgeon is directing his attention. The CTS MIDCAB. System serves asimilar function to the ENDOCABG retractor, but is more complex. Thedesignation CABG refers to “coronary artery bypass graft.”

Major disadvantages of these systems include their limited positioning,complexity, and lack of reusability. It has now been discovered that theshortcomings of the retractors that are known in the prior art can beovercome with a new design as set forth in the following description.

SUMMARY OF THE INVENTION

One aspect of this invention is an adjustable surgical retractor thatcomprises

(a) two handles suitable for grasping positioned opposite each other andconnected so that the handles move reciprocatingly relative to eachother,

(b) a head connected to each handle so that each head movesreciprocatingly relative to the other,

(c) a means for locking the heads at a preset distance from each other,and

(d) a blade connected to each head, each blade having a width, depth andthickness so that the width extends substantially parallel to the lengthof the handle and the depth extends downward from the top of the headwherein the blades taken together at the position of closest proximityto each other are of a size suitable to be inserted into a surgicalincision in a patient undergoing a surgical procedure then spread apartto form an elongated access opening through which a medical instrumentmay be inserted to perform exploratory or surgical procedures.

Another aspect of this invention is a blade suitable for use as part ofa surgical retractor, which blade comprises a biocompatible materialhaving dimensions defined by a width, depth and thickness, the width andthe depth defining an first and an second face separated from each otherby the thickness of the blade, wherein the blade has a connector meansfor attaching to a head means of the surgical retractor.

Another aspect of this invention is a method of providing surgicalaccess to a patient, which method comprises making a surgical incisionthrough the skin and soft tissue of the patient,

inserting two blades of a surgical retractor perpendicularly through theincision, and

spreading the blades of said retractor to provide a relativelysymmetrical, elongated channel for internally accessing said patient,said channel being defined by said blades wherein the internal faces ofthe blades have a concave surface to define a substantially ovoidchannel, each blade having a smooth, continuous upper surface.

Another aspect of this invention is a method of performing minimallyinvasive surgery on a patient, which method comprises

making a surgical incision through the skin and soft tissue of thepatient,

inserting two blades of a surgical retractor, perpendicularly throughthe incision,

spreading the blades of said retractor to provide a relativelysymmetrical, elongated channel for internally accessing said patient,said channel being defined by said blades wherein the internal faces ofthe blades have a concave surface to define a substantially ovoidchannel, each blade having a smooth continuous upper surface,

inserting a surgical instrument through said substantially ovoidchannel, and

performing a surgical procedure using the surgical instrument soinserted.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of the surgical retractor of this invention in theclosed position with the proximal ends of the retractor shown at thebottom of the page and the distal end at the top.

FIG. 1A is the side view taken along line 1A-1A′ shown in FIG. 1.

FIG. 1B is an end view along line 1B-1B′.

FIG. 2 is a top view of the retractor of this invention with the bladesspread open.

FIG. 3 is a top view of a retractor of this invention having fingerholds on the proximal grasping end of the retractor, the retractor beingin the closed position.

FIG. 3A is a top view of the retractor of FIG. 3 shown in the openposition.

FIG. 4 is a side view along lines 4F-4F′ of the retractor of FIG. 3.

FIG. 5 is a top view of the surgical retractor of this invention similarto FIG. 3 but with a shorter handle.

FIG. 6A is a top view of the retractor of this invention shown withoutthe blades positioned on the head region of the handles and in theclosed position.

FIG. 6B is a top view of the retractor of FIG. 6A in the spread openposition.

FIG. 6C shows the head region of the retractor in FIG. 6A havingremovable blades attached to the head member on a post as the connectormeans.

FIG. 6D is a side view of FIG. 6C.

FIG. 6E shows the head members of the surgical retractor with swivelingblades on the head member in the closed position.

FIG. 6F shows the head members in of FIG. 6E in the open position.

FIG. 7A shows an alternative design for the retractor of this inventionwhere the handle has a roughened surface for improved grasping.

FIG. 7B is a side view along line 7B-7B′ and showing a textured surfaceon the outside face of the blade.

FIG. 7C is a cross-sectional end view along line 7C-7C′ of the bladespositioned together in the head member of the surgical retractor.

FIG. 7D is an end view along line 7D-7D′ showing the conjunction of theblades of the surgical retractor.

FIG. 7E shows the surgical retractor of FIG. 7A with the blades spreadin the open position and the handles pulled together.

FIG. 8A is a perspective view of a blade of this invention having aslight curvature with a concave inner surface and a resilient outersurface.

FIG. 8B shows the relative distance of the upper and lower lip at thetop and bottom of the blade.

FIG. 9A shows a pair of disposable retractor blades suitable for usewith the retractor of FIGS. 1 through 7.

FIG. 9B is an alternative design for a pair of disposable retractorblades.

FIG. 9C is another design of the disposable retractor blade useful inthis invention.

FIG. 9D shows a pair of disposable retractor blades as shown in 9A asthey would look if they were flexed and attached to the retractor headand spread in an open position pushing against a patient's ribs.

FIG. 9E shows the blades of FIG. 9B as they would appear if they wouldbe spread apart and used to spread the ribs in accordance with theprocess of this invention.

FIG. 9F is another design for the disposable retractor blades for use inthis invention.

FIGS. 9G-9I show the various positions blades that swivel on the postsof FIG. 6C or 6D could take.

FIG. 9J shows tapered blades viewed along lines 9J-9J′ in FIG. 9C.

FIG. 10A shows a perspective view of a design of blades having a lip atthe top and bottom of the blade curling toward the convex face.

FIG. 10B shows a profile view of the blades showing the lip.

FIG. 11 shows the positioning of an incision in the intercostal space asused in the process of this invention.

FIG. 12A shows two retractors in place and stabilized by interconnectingbar shown in FIGS. 12B and 12C.

FIG. 12B shows an appropriate interconnecting bar.

FIG. 12C shows a notched interconnecting bar for interconnecting tworetractors and stabilizing them.

FIG. 13 shows entry incision ports suitable for use for with theretractor of this invention in comparison to other trocars which aregenerally used for minimally invasive surgery.

FIG. 14A shows the greater degree of freedom that a surgeon would havein using the retractor of this invention as compared to a trocar shownin FIG. 15.

FIG. 14B is a cross-section of the elongated access opening.

FIG. 15A shows a trocar inserted into a patient between the ribs.

FIG. 15B shows the small cross-section of 15A.

FIG. 16 shows a patient positioned for a lateral incision using aretractor of this invention.

FIGS. 17A-17F show various preferred embodiments of the surgical bladesof this invention.

DETAILED DESCRIPTION AND PRESENTLY PREFERRED EMBODIMENTS

While the description of the surgical retractor of this invention willbe discussed primarily in relation to cardiac surgery procedures, itshould be understood that the surgical retractor of this invention willfind use in not only cardiac surgery but also laparoscopic surgery inwhich a surgeon wishes to gain access to an internal cavity by cuttingthe skin and going through the body wall in order to keep the incisionspread apart so that surgical instruments can be inserted.

Thus the surgical retractor can find use in providing surgical accessgenerally where a limited incision is desired. It is useful forsubcutaneous access as well as for surgically accessing various bodycavities such as the abdominal region, the thoracic region and theextremities.

It should also be understood that the surgical retractor of thisinvention can be used for direct access to an internal organ forsurgical purposes with direct viewing of the work that's going on but itis preferably used in conjunction with video assisted cardiac surgery.In such a case, the surgical retractor of this invention is used incombination with a video endoscope that is positioned through a similarsurgical retractor, a trocar or a percutaneous access opening whichallows the scope to be positioned such that the internal work on thearea to be operated on is transmitted to a video screen and the surgeonthen performs the operation by viewing the screen and judging the use ofthe instruments with the assistance of the video endoscope. The surgicalretractor has particular value in minimally invasive surgical techniquesused in cardiac surgery.

One aspect of this invention is an adjustable surgical retractor. Theretractor comprises

(a) two handles suitable for grasping positioned opposite each other andconnected so that the handles move reciprocatingly relative to eachother,

(b) a head connected to each handle so that each head movesreciprocatingly relative to the other,

(c) a means for locking the heads at a preset distance from each other,and

(d) a blade connected to each head, each blade having a width, depth andthickness so that the width extends substantially parallel to the lengthof the handle and the depth extends downward from the top of the headwherein the blades taken together at the position of closest proximityto each other are of a size suitable to be inserted into a surgicalincision in a patient undergoing a surgical procedure then spread apartto form an elongated access opening through which a medical instrumentmay be inserted to perform exploratory or surgical procedures.

The blades, when taken together at the position of closest proximity toeach other are of a size suitable to be inserted into a surgicalincision in a patient undergoing a surgical procedure then spread apartto form an elongated, ovoid access opening through which a medicalinstrument may be inserted to perform exploratory, diagnostic orsurgical procedures.

Preferably, the surgical retractor is designed so that each blade has aninside face and an outside face. The inside face of each blade faces theinside face of the other blade and the outside face of each blade isdesigned to (i) minimize the trauma to the patient's body at theincision when the head means and blades are spread apart, (ii) stabilizethe blades in the incision and (iii) allow customization for eachpatient's anatomy.

Referring now to FIG. 1, one sees the adjustable surgical retractor ofthe invention generally designated as 2. The retractor is characterizedby having a elongated handle 4R and 4L for the right and left side asshown in FIG. 1. The elongated handles have a grasping end shown as 6Land 6R for the left and right sides of the device which are proximal tothe user. On the opposite end, distal from the grasping handle are theends 8L and 8R, again indicating the left and the right side as shown inthe figure. Generally, the ends 8L and 8R when in the closed positionshown in FIG. 1 will be in contact and there will generally be a spacebetween opposing jaws of the device 9L and 9R. The handles which aresuitable for grasping and are positioned opposite to each other arepivotally connected at pivot point which will have a male member pivotpin 10 which will correspond to a female receiving member 11 to allowthe pivoting to take place. Thus the opposite ends 8L and 8R that aredistal to the grasping handles comprise heads that are connected to eachelongated handle so that each head moves reciprocatingly relative to theother. When handles 6L and 6R are drawn together as shown in FIG. 2, thedistal ends or heads 8L and 8R are spread apart. A key to the utility ofthis particular design is the presence of a locking means to lock theheads at a preset distance from each other. The means shown in this caseis a ratchet segment 14 having teeth 16 along the arcuate member 15interconnecting handles 4L and 4R. Working in concert with the ratchetsegment 14 and its corresponding teeth 16 is a corresponding pawl member18 which is pivotally mounted at pivot 19, not shown, working in concertso that the teeth 20 on pawl 18 (as shown in FIG. 2) are complementaryto the teeth 16 and provide a means for locking the heads at a presetdistance from each other. Because of the numerous teeth 16 along ratchetmember 14 the distance between head members 8L and 8R can varysignificantly and in small incremental amounts. When pawl member 18 isdisengaged from the ratchet segment 14 by not having the teeth incontact, tensioning means 12 tends to keep the handles 6L and 6R apart.Thus if the teeth are not engaged, the handles will tend to be spreadapart by the tensioning means so that the heads 8L and 8R are generallyin contact and ready for insertion prior to a surgical operation.

Each head means (which is shown as being unitary with the handle) has aconnector means suitable for connecting a connector blade 22 to thecorresponding heads 8L and 8R of elongated handles 4L and 4R. A blade 22is connected to the head member of the elongated handle 4 by a connectormeans not shown, with each blade 22 having a width, depth and thicknessdimensions that define the blade. The width, for purposes of thisinvention, is said to extend substantially parallel to the length of thehead or handle. The top of the blade as seen as 23 in FIG. 1 such thatwhile in use, the blade would be inserted into the surgical incision andthe top edge 23 would remain outside the patient's surgical opening. Thedepth of the blade would extend downward from the top 23 of the bladeinto the surgical incision. Thus by looking at the side view of FIG. 1A,the bottom of the blade 22 would be shown as 24. The thickness of theblade is shown in FIG. 1 by the approximate extension dotted line at thehead of the retractor device. The bottom of blades 24, when takentogether at the position of closest proximity to each other as shown inFIG. 1, are of a size suitable to be inserted into a surgical incisionin a patient undergoing a surgical procedure. Once inserted, the bladesare then spread apart as shown in FIG. 2 to form an elongated accessopening through which a medical instrument may be inserted to performexploratory or surgical procedures as discussed hereinafter. The view ofFIG. 1A of the surgical retractor of this device is a side view alonglines 1A to 1A′ in FIG. 1A while an end view along lines 1B to 1B′ isshown in FIG. 1B. The numbers in each of FIGS. 1, 1A, 1B and 2 alldesignate similar parts of the device.

Turning now to FIG. 3, one can see an alternative configuration for thesurgical retractor of this invention. In FIG. 3, the same numerals thatare used in FIG. 1 are used as well. The only difference here is thatthe grasping handle 6L and 6R has a slightly modified design that allowsthe surgeon using the retractor to insert a thumb and other digit tograsp the handle at 7L and 7R of the proximal end 6L and 6R. Otherwisethe operation of the retractor is the same as that shown in FIG. 1 andFIG. 2. FIG. 4 is a side view of the surgical retractor along lines 4Fand 4F′ showing the inserted edge 24 of blade 22 of the retractor. FIG.3A shows the surgical retractor in the open position where the bladesare spread apart.

Referring again to FIGS. 1, 1A, 1B and 2, one can see certain preferredaspects of the invention. Each blade for the retractor has an insideface and an outside face. The outside face can be seen in FIGS. 1A and1B. The outside face of the blade is designed to minimize the trauma tothe patient's body at the incision when the head means and the blade arespread apart and to further stabilize the blade in the incision. Tominimize the trauma and stabilize the blade, it is preferred that theoutside surface of the blade be of a finish that is slightly irregularand preferably is of a texture that is less traumatizing than a smooth,hard texture. In general the blades are made of a material which isstrong enough to withstand the pressure of opening the retractor in themanner in which it is to be used. For example, if an incision is made inbetween the fourth and fifth ribs in the intercostal area, the ribs willhave to be spread apart and the blades will have to be strong enough towithstand the pressure of gently spreading apart the ribs. Thus materialfor the blades may be of any material which is biocompatible with thepatient's body and using it in the incision. The materials that can beused are stainless steel, plastic such as polyvinyl chloride (PVC),polyethylene, polyesters of various sorts, polycarbonate, teflon coatedmetal and the like. In addition to, or as an alternative to, theirregular surface of the outside face of the blade, the outside face maybe padded or resilient to a certain extent to minimize the trauma to thesurrounding tissue as it is spread open. Thus the blade may be of alaminated construction which has a stronger material on the inner facewith the outer face having a spongier or padded characteristic.

Preferably, the surgical retractor blade will be designed so that theupper edge 22 of each blade when spread apart has a concavely smoothsurface corresponding to a concave surface of the interface which willbe suitable for resting a surgical instrument against. This allows formuch better movement of the instruments, e.g. in dissection of aninternal mammary artery (IMA) and suturing of vessels. This can be seenin FIGS. 1 and 2, particularly in FIG. 2 where the concave surface isshown as number 25 for each blade connected to head 8L and 8R.Preferably there will be a lip at both the top edge 23 and the bottomedge 24 as shown in FIG. 1B. A slightly rolled edge is important formaintaining the blade in place so that the heads are spread open asshown in FIG. 2. In some instances it is preferred that the blade is ofa flexible material such as a plastic with the outer face having aslightly irregular surface to stabilize the blade in the incision. Inthat case, the blades, when inserted onto the heads of the retractor,can be essentially parallel to each other but as the blades are spreadapart, the ends would tend to bend towards each other forming theconcavity shown in FIG. 2.

Alternatively, the blades may be preformed so that they have a lip orridge on both the top 23 and the bottom 24 and have a preformedconcavity that forms as the two interfaces rest against each other. Thiscan be seen at FIGS. 8A, 8B, 10A and 10B. In this manner where eachblade is rigid and the inner face of each is concave relative to theother where the outwardly protruding lip or ridge 23 on the upper andlower edge 24 of each blade, the blades are maintained in the incisionwhen the head and the blades are spread apart after insertion into thepatient's surgical incision. Where a patient's abdominal region is beingaccessed the lower lip will have to extend more than if the thoracicregion is being accessed through the rib cage. Generally the lip at thetop edge 23 shown in FIG. 10B will extend out about ⅜″ with the bottomlip 24 extending about ⅛″ when entering intercostally. If abdominalaccess is desired the lower lip 24 will have to extend out further. Thedimensions shown in FIG. 8B will vary with individual patients. However,a particularly useful size for X is about 1.5 inches, for Y is about ⅜inch and for Z is about ⅛ inch. A preferable aspect to the surgicalretractor of this invention is that the blades are removable. Thesurgeon can select a blade having the desired width and depth to createexactly the size opening he or she wants, depending on a patient's size,shape, age, anatomy, etc., and the type of operation to be performed,e.g. lifting the left IMA for dissection. This is a particularlyattractive aspect of the invention because the handles and the rest ofthe mechanism can be made of a durable, sterilizable material such asstainless steel. The blades can be made of a material that isre-sterilizable, and may be reusable or disposable, thus making thedevice easier and cheaper for the surgeon to use the device. Forexample, at the present time the commercially available devices throughU.S. Surgical and CTS are very expensive and can be used only oncebecause they have numerous parts and they all cannot be resterilized. Byhaving removable blades 22 that can be disposed of, the surgicalretractor 2 can be used multiple times by simply sterilizing then addingnew disposable blades.

Preferably, the connector means on the head member of the surgicalretractor that is suitable for connecting the blade is simply a malepivot pin as shown in FIGS. 6A-6F. Here the pivot pin, which is at thedistal end of the surgical retractor, is shown as 26L and 26R. Thesurgical retractor blade which is removable has a reciprocal femalereceiving port 27 into which the pivot pin will slip. The pivot pin maybe designed to lock the blade in place or to allow the blade to rotateas shown in FIG. 6E-6F. When the surgical retractor's handles areextended outwardly as shown in FIG. 6A, the blades would be together asshown in FIG. 6E where the male pivot pin seated in the female receivingport 27 as shown. As the proximal ends 6L and 6R are pulled togetherthrough grasping means 7L and 7R, the blades are pulled apart and canswivel slightly to adjust to the tension in the process of spreadingapart the ribs.

The blades which are useful in the surgical retractor of this device areof a width, depth and thickness which will allow the surgeon access tothe internal organs of the patient once an incision is made. Generally,the width of each blade may vary between about 1 inch to about 4 inchespreferably 1 inch to about 3 inches. The depth will be of a sufficientdepth to be adequately retained within the surgical incision when thehead of the retractor are spread apart. Generally this depth will beabout 1 inch to about 3 inches depending on the size and weight of thepatient. The thickness, of course, will be of sufficient thickness towithstand the pressures of spreading apart the ribs of the patient ifthat's how the retractor is to be used. The thickness will depend on thestrength and flexibility of the material used in making the blade.Generally, the thickness will be about one-eighth inch to aboutthree-quarters of an inch.

When the blades are flexible, it is preferable that the male pivot pinreceiving means is designed to frictionally receive the blade and retainit without pivoting. If, however, the material is of a metallic naturesuch as stainless steel and is inflexible, then it's preferable that thepivot pin would allow the inflexible blade to pivot freely on the post.Thus if blades of the approximate dimensions mentioned above are used itcan be seen that the surgical opening could have a length of about 1inch to about 4 inches and a width of about one-quarter inch to abouttwo inches.

Turning now to FIG. 7A-7E one sees a variation on the design of theretractor of this invention. Here, the same numbers designate the sameparts as in the previous FIGS. 1 through 6F. The difference between thedesign in FIG. 1 and FIG. 7A is simply that the handles 4L and 4R havenotches designated at 5L and 5R to provide a better grasp for thesurgeon using the retractor.

These can be seen in both FIGS. 7A and 7B, 7B being the side view alonglines 7B and 7B′. In addition, the handles 6R and 6L may have anadditional notch designated as 28 for receiving a stabilizing bar whichthe surgeon can use to connect two surgical retractors of thisinvention. This is discussed hereinafter in greater detail. Thecross-sectional end view of the device along lines 7C, 7C′ shows across-section of the blade having the top edge 23 slightly expanded andcurved outwardly to form a lip at the top edge. At the bottom edge 24similarly the blade is curved outwardly to form a smaller lip. By havingthese lips, the retractor when used will tend to stay in place to agreater extent than in the absence of the lips. By viewing FIG. 7D,which is an end-on view, along lines 7D, 7D′, one can see the end viewshowing the outer side 21 of the blade 22 having a resilient materialattached thereto to minimize the trauma and to maximize the friction toassist in maintaining the blade in place when in use. FIG. 7A shows theretractor with the heads closed while FIG. 7E shows the retractor withthe head and the blades in an open position spread apart. Of course, thelocking mechanism for maintaining the retractor in a spread, openposition operates in the same manner as explained for FIGS. 1 through 6.

Turning now to FIG. 8A, one can see a close-up of a blade having theconcave inner surface and convex outer surface along with a top lip 23which is more exaggerated than the bottom lip 24. In general, the toplip might be anywhere from a quarter to a three-quarters of an inch,generally about three-sixteenths of an inch at the widest point with thebottom lip generally being somewhat less than that amount, about aneighth of an inch, to about a half an inch, generally about an eighth ofan inch. These dimensions are further shown in FIG. 8B.

Turning now to FIGS. 9A through 9F, one can see a perspective view thedesigns of the pairs of blades that would be used in the retractor ofthis invention. These blades are designed to be disposable and may bemade of any materials that would be appropriate for the constructionshown. In FIG. 9A, one sees a set of blades that have a top edge 23 anda bottom edge 24 along with a distal edge 29 and a proximal edge 30.Here, both the distal and proximal edges are shown as being rounded. Theinside face 25 of the two blades is shown to be essentially straight,although it can be designed to be slightly convex as shown in FIG. 9B,if desired. A blade when attached to the connector means of the headmember of the surgical retractor and expanded against the ribs when theretractor is in use will generally provide a convex outer surface 21 anda concave inner surface when the blade is of a flexible material. Thisis thought to be due to the fact that the female receiving port 27 inthe blade 22 would receive the male pivot pin which would be thestrongest portion of the blade and which would provide the outwardstress to spread the ribs. Thus, the central portion of the blade wouldtend to spread out further than the distal and proximal edges, 29 and 30respectively.

In FIG. 9B, one can see that there is a taper from the central portionof blade 22 where the female receiving port 27 is found to the distaledge 29 as well as to the proximal edge 30. Here the blade is somewhatan elongate, ovoid in shape and would take a shape similar to that shownin 9E when used with the surgical retractor in the manner designed.Alternatively, the design shown in 9C in essence shows a crescent shapefor each of the blades wherein the opposing faces of the internal sides25 are essentially parallel while the outside face 21 of each blade isconvex. When in use, this too would take the configuration generallyshown in FIG. 9E. Still another configuration is shown in FIG. 9F. Herethe inner faces 25 are essentially parallel to the outer faces 21 andthe edges of the proximal and distal edges 30 and 29, are somewhatblunter than those shown in either FIGS. 9A, 9B or 9C. This blade wouldtake a configuration shown in FIG. 9D. In each of the disposable bladesshown in FIGS. 9A through 9F, when viewed along line 9J-9J′ as shown inFIG. 9C, the lower edge 24 is slightly tapered to minimize the amount ofspace needed for the initial insertion of the blades as attached to thesurgical device.

Particularly useful configurations of the disposable blades of thisinvention are shown in FIG. 17A-17F. In the figures the numbers used todesignate the part are the same as in FIGS. 9A-9J. Here in FIG. 17A onesees a blade which is thicker in the midsection than at the endssomewhat similar to the configuration in 9B and 9C. The view here is adirect top down view showing distal end 29 and proximal end 30 alongwith the inside face 25 and outside face 21. The top side is shown as 23and the female receiving means is shown as 27. When the blade is fittedon to the corresponding male fastening means or post and the blades ofthe surgical retractor are spread apart the blade to the left in FIG.17A will take the configuration shown in FIG. 17B as compared toconfiguration of FIG. 17A which shows the blade at rest. The primaryspreading force will be at the center of the blade 27 and an elongatedoval shaped opening will be formed as a result of the spreading of theblades. Turning now to FIG. 17C one sees a slightly different designwherein an internal channel 62 which aids in the cushioning effect ofthe blade. Here when the blade is attached to the head means through themale pivot pin which fits into the female receptor 27 and the retractoris spread apart to spread apart tissue and ribs as earlier discussed theblade will flex as shown in FIG. 17D and the cutout channel willstraighten as shown. The channel 62 has a slightly curved part 63 thatwill straighten somewhat to form the silhouette shown in FIG. 17D. Thusthe outer wall 21 prevents the blade from flexing too much when expandedand the channel 62 provides a cushioning effect so that the inner face25 pushes against the outer wall 21 by compressing channel 62 whilemaking a greater opening between the convex surfaces 25 of the blade.Alternatively in FIG. 17E one can see the channel extending from theproximal edge of the blade 29 to the distal edge of the blade 30. Herewhen the blade is attached to the male connector means which is insertedinto the female receptor and the retractor and expanded then the designwhich has an essentially flat face 35 changes to that silhouette shownin FIG. 17E. Here the outer wall defined by 21 bears the force of theflexion of the blade and prevents the limbs of the blade from flexingtoo much. The air channel compresses to add some cushioning effect andflexibility against the tissues to reduce the trauma to the tissues.

In use, the surgical retractor of this invention can be employed eitherin the anterior or lateral position on the chest for thoracicretraction. Preferably, it is employed laterally and in surgery thepatient would be positioned to expose the lateral side of the patient tothe doctor. This position is shown in FIG. 16 where the arm 31 of thepatient is raised to expose the lateral side 32 of the patient to thedoctor. The back 33 is positioned as shown. In the semi-cutaway view ofFIG. 11 one can see how the retractor of this invention would work. Herethe patient would be positioned similar to that shown in FIG. 16 withthe arm 31 raised to expose the lateral side of the patient. The ribsshown as numbers 34 through 44 are attached to the spine shown roughlyas 45 with intercostal spaces between the ribs. Incisions 46 and 47 areshown as being made between ribs 4 and 5 and 7 and 8. Once the incisionis made, the retractors are used in accordance with FIG. 12. Here, theretractors are shown inserted with the head spread open to provideaccess for the surgeon to enter the thoracic cavity. The retractors maybe connected in accordance with the use of connecting rods shown inFIGS. 12B or 12C and connected in accordance with the use of a retractorhaving a notch in the handle similar to that shown in FIG. 7B. Theconnecting rod may be of a design shown in FIGS. 12B and 12C asconfiguration 48 or 50. Once the retractors 2U and 2L are in place,creating the elongated opening or windows, into the thoracic cavity, inintercostal spaces between the fourth and fifth ribs shown as 46 inbetween the 7th and 8th ribs shown as 47. The positioning for a bar suchas that shown in 48 and 50 in FIGS. 12B and 12C respectively, may beaccomplished by several ways. In one mechanism, a screw down mechanismis used, shown as 48 a and 48 b in FIG. 12C. By using the positioningbars with the retractors, the retractors are secured to enable theretractors to be angled at the appropriate angle toward the heart orother structure to enable a diagnostic or therapeutic procedure is to becarried out. The angles of retractors to 2U and 2L is such that a 5degree to 50 degree angle of the instruments relative to a perpendicularline through the opening is achieved. This provides the surgeon with anangle of access and a range of movement that is similar to that of anopen heart surgical procedure. Locking screws 49A and 49B are shownwhere the solid bar 48 is rigid. While the bar is shown as straight itmay optionally be slightly curved to contour to the shape of the ribcage. In FIG. 12C, positioning bar 50 is made of interlocking metalpieces with an interior wire that when tightened locks the position ofthe shape of the bar into place and the securing screws shown as 51 aand 51 b are shown protruding from one side of the interlocking metalpieces.

FIG. 13 indicates the difference in the elongated opening or windowapproach and the port method reported by Sterman, et al. Elongatedopenings 46 and 47 show greater exposure and flexibility compared withthe trocar port in performing the work. Using the trocars generally aport will be located at positions 52, 53, 54 and at 46. Alternatively,if a minimally invasive direct coronary artery bypass MIDCAB incisionsuch as a sternotomy incision is used, it is done at 55. Whatever isused it is useful to provide a percutaneous opening 56 for a view scopeand one or more additional instruments required for traction ormanipulation of the thoracic cavity. It should be understood that theinvention retractor can also be used for MIDCAB surgery where the entryis made anterially as compared to laterally.

Turning now to FIG. 14, one can see the greater degree of manipulationthat a doctor would have using the surgical retractor of applicant'sinvention as compared to the trocar. With the surgical retractor one cansee that one obtains a wider range of motion for a surgical instrumentshown as 58. The view here is of the cross-section, end-on view thatwould be similar to that shown in FIG. 7E along lines 7C-7C′ shown inFIG. 7 a. Here you can see the top 23 of blade 22.

The bottom of the blade 24 sits inside the thoracic cavity. Ribs 4 and 5are shown as 37 and 38. The flexibility of the opening 46 in such a caseshould be compared with the lack of flexibility in FIG. 15 where atrocar is used to enter the thoracic cavity. This is visualized betterby viewing a top-down view of FIG. 14A that shows the cross-section ofelongate opening 46 compared to the cross-section of opening 60 oftrocar 59 in FIG. 15A.

Having described the details of the surgical retractor of thisinvention, one can now consider another aspect of the invention, namelya method of providing surgical access to a patient. The method comprisesmaking a surgical incision through the skin and soft tissue of thepatient, inserting two blades of a surgical retractor perpendicularlythrough the incision, and spreading the blades of said retractor toprovide a relatively symmetrical, elongated channel for internallyaccessing said patient. The channel is defined by the blades wherein theinternal faces of the blades have a concave surface to define asubstantially ovoid channel, each blade having a smooth, continuousupper surface. The method of course, is best performed using thesurgical retractor described hereinbefore.

The method is particularly valuable in cardiac surgery where thesurgical incision is made intercostally for access to the patient'sthoracic region. Generally, at least two surgical incisions are madeintercostally and sufficiently spaced apart to allow for the insertionand spreading of the blades of two of said surgical retractors. Eachpair of spread blades then provide a relatively symmetrical, elongatedchannel for accessing the internal thoracic region of the patient.Preferably, two surgical incisions are made laterally on said patient,although the incisions may also be made anteriorly on said patient. Asshown in FIG. 12A, the two surgical retractors may be interconnected bya stabilizing bar to fix their positions relative to the other. Toprovide viewing access to the patient's thoracic cavity a third incisionis made to insert an image transmission means to transmit an image ofthe patient's internal thoracic region.

Another aspect of this invention is a method of performingminimally-invasive invasive surgery on a patient. The method comprises

making a surgical incision through the skin and soft tissue of thepatient,

inserting two blades of a surgical retractor, perpendicularly throughthe incision, spreading the blades of said retractor to provide arelatively symmetrical, elongated channel for internally accessing saidpatient (the channel is defined by the blades wherein the internal facesof the blades have a concave surface to define a substantially ovoidchannel, each blade having a smooth continuous upper surface),

inserting a surgical instrument through said substantially ovoidchannel, and

performing a surgical procedure using the surgical instrument soinserted. The method preferably employs the retractor described herein.The size and shape of the retractor blades are chosen for the exact sizeopening desired. The smooth continuous upper surface allows the surgeonto carryout the surgical procedures more easily. This method isparticularly suited for cardiac surgery when said patient is maintainedon a cardiopulmonary by-pass machine and the surgical incision is madeintercostally for access to the patient's thoracic region. Preferably atleast two surgical incisions (preferably lateral) are made intercostallyand sufficiently spaced apart to allow for the inserting and spreadingof the blades of two of said surgical retractors, each pair of spreadblades providing a relatively symmetrical, elongated channel foraccessing the internal thoracic region of the patient.

1. An adjustable surgical retractor that comprises (a) two handlessuitable for grasping positioned opposite each other and connected sothat the handles move reciprocatingly relative to each other, (b) a headconnected to each handle so that each head moves reciprocatinglyrelative to the other, (c) a means for locking the heads at a presetdistance from each other, and (d) a blade connected to each head, eachblade having a width, depth and thickness so that the width extendssubstantially parallel to the length of the handle and the depth extendsdownward from the top of the head wherein the blades taken together atthe position of closest proximity to each other are of a size suitableto be inserted into a surgical incision in a patient undergoing asurgical procedure then spread apart to form an elongated access openingthrough which a medical instrument may be inserted to performexploratory or surgical procedures.
 2. The surgical retractor of claim 1wherein each blade has an inside face and an outside face, said insideface of each blade facing the inside face of the other blade and theoutside face of each blade designed to (i) minimize the trauma to thepatient's body at the incision when the head and blades are spread apartand (ii) stabilize the blades in the incision.
 3. The surgical retractorof claim 1 wherein the upper edge of each blade when spread apart has aconcavely smooth surface corresponding to a concave surface of the innerface and is designed to stabilize a surgical instrument when suchinstrument contacts it.
 4. The surgical retractor of claim 3 whereineach blade comprises a flexible material with the outer face having atextured surface to stabilize the blade in the incision.
 5. The surgicalretractor of claim 4 wherein when the inner faces of the blades are inclosest proximity, the width of each blade is parallel to the other. 6.The surgical retractor of claim 3 wherein each blade is a flexiblematerial and the outer surface comprises a resilient material.
 7. Thesurgical retractor of claim 1 wherein each blade is rigid and each innerface is concave relative to the other with an outwardly protruding lipon the upper and lower edge of each blade to assist in maintaining theblades in the incision when the head and blades are spread apart afterinsertion into the patient's surgical incision.
 8. The surgicalretractor of claim 1 wherein the blades are disposable.
 9. The surgicalretractor of claim 1 wherein the width of each blade is about one inchto about four inches, the depth is about one inch to about three inchesand the thickness is about one-eighth inch to about three-quarters of aninch.
 10. The surgical retractor of claim 1 wherein when the head andblades are spread apart a surgical opening is formed having a length ofabout one inch to about four inches and a width of about one-quarterinch to about two inches.
 11. The surgical retractor of claim 1 whereineach blade is connected to each head by a post and a correspondingreceptacle.
 12. The surgical retractor of claim 11, wherein each bladecan swivel on each post.
 13. The surgical retractor of claim 11, whereineach post is formed of a locking pin, thereby preventing the blade fromswiveling on the post.
 14. The surgical retractor of claim 11 whereinsaid post is frictionally held in said receptacle.
 15. The surgicalretractor of claim 11 wherein the blade is removably connected to thehead.
 16. A method of providing surgical access to the internal thoracicregion of a patient, which method comprises making an intercostal,surgical incision through the skin and soft tissue of the patient,wherein the incision is sufficiently sized to allow for the insertion ofa surgical retractor in the incision; providing a surgical retractorincluding: (a) two handles suitable for grasping positioned oppositeeach other and connected so that the handles move reciprocatinglyrelative to each other; (b) a head connected to each handle so that eachhead moves reciprocatingly relative to the other; (c) a means forlocking each head at a preset distance from the other; and (d) a bladeconnected to each head, each blade having a width, depth and thicknessso that the width extends substantially parallel to the length of thehandle and the depth extends downward from the top of the head;inserting two blades of said surgical retractor perpendicularly throughthe incision; and spreading the blades of said retractor to provide arelatively symmetrical, elongated channel for accessing the internalthoracic region of the patient, said channel being defined by saidblades wherein the internal faces of the blades have a concave surfaceto define a substantially ovoid channel, each blade having a smooth,continuous upper surface.
 17. The method of claim 16, wherein at leasttwo surgical incisions are made intercostally and sufficiently spacedapart to allow for the insertion and spreading of the blades of two ofsaid surgical retractors, each pair of spread blades providing arelatively symmetrical, elongated channel for accessing the internalthoracic region of the patient.
 18. The method of claim 16, wherein saidtwo surgical incisions are made laterally on said patient.
 19. Themethod of claim 16, wherein said two surgical incisions are madeanteriorly on said patient.
 20. The method of claim 16, wherein said twosurgical retractors are interconnected by a stabilizing bar to fix theirpositions relative to the other.
 21. The method of claim 16, wherein athird incision is made to provide access to the patient's thoraciccavity sufficient to insert an image transmission means to transmit animage of the patient's internal thoracic region.
 22. A method ofperforming minimally-invasive cardiac surgery on a patient, which methodcomprises providing a surgical retractor including: (a) two handlessuitable for grasping positioned opposite each other and connected sothat the handles move reciprocatingly relative to each other, (b) a headconnected to each handle so that each head means moves reciprocatinglyrelative to the other, (c) a means for locking each head at a presetdistance from the other, and (d) a blade connected to each head, eachblade having a width, depth and thickness so that the width extendssubstantially parallel to the length of the handle and the depth extendsdownward from the top of the head; making an intercostal surgicalincision through the skin and soft tissue of the patient, wherein theincision is sufficiently sized to allow for the inserting and spreadingof the blades of said surgical retractor, inserting two blades of asurgical retractor, perpendicularly through the incision, spreading theblades of said retractor to provide a relatively symmetrical, elongatedchannel for accessing the internal thoracic region of said patient, saidchannel being defined by said blades wherein the internal faces of theblades have a concave surface to define a substantially ovoid channel,each blade having a smooth continuous upper surface, inserting asurgical instrument through said substantially ovoid channel, andperforming a surgical procedure using the surgical instrument soinserted.
 23. The method of claim 22, wherein said surgery is cardiacsurgery and said patient is maintained on a cardiopulmonary by-passmachine.
 24. The method of claim 23, wherein at least two surgicalincisions are made intercostally and sufficiently spaced apart to allowfor the inserting and spreading of the blades of two of said surgicalretractors, each pair of spread blades providing a relativelysymmetrical, elongated channel for accessing the internal thoracicregion of the patient.
 25. The method of claim 22, wherein said twosurgical incisions are made laterally on said patient.
 26. The method ofclaim 22, wherein said two surgical incisions are made anteriorly onsaid patient.
 27. The method of claim 22, wherein said two surgicalretractors are interconnected by a stabilizing bar to fix theirpositions relative to the other.
 28. The method of claim 22, wherein athird incision is made to provide access to the patient's thoraciccavity sufficient to insert an image transmission means to transmit animage of the patient's internal thoracic region.
 29. The method of claim28, wherein the surgery is performed by the surgeon by manipulating theinstruments viewing the image surgery so transmitted by the transmissionmeans.